Any pages that become mapped into the address space of the process after a
call to munlockall() shall not be locked, unless there is an intervening
call to mlockall() specifying MCL_FUTURE or a subsequent call to mlockall()
specifying MCL_CURRENT
If pages mapped into the address space of the process are also mapped into
the address spaces of other processes and are locked by those processes, the
locks established by the other processes shall be unaffected by a call by
this process to munlockall()
Upon return from the munlockall() function, all currently mapped pages of
the process' address space shall be unlocked with respect to the process'
address space
The memory residency of unlocked pages is unspecified
If it is supported by the implementation, the munlockall() function shall
always return a value of zero
If it is not supported by the implementation, the munlockall() function
shall return a value of -1 and set errno to indicate the error